But the 6-foot-6, 242-pounder, who outran defensive backs throughout his Arkansas career, said nobody else believed him until he actually did.
"A lot of the coaches are expecting me to run a (4.6-second 40) or a high 4.5," Jones said Sunday night. "To be able to run an (unofficial 4.37), in my mind I knew I could do it. I ran a 4.41 about three weeks ago.
"It's just cool that all the other people didn't think I could and I was able to."
The combine wrapped up Tuesday afternoon at the Indiana Convention Center and Jones' performance in the 40-yard dash Sunday remained one of the most intriguing stories during the week-long event.
Jones ran the fourth fastest time among offensive players when he was officially clocked at 4.40 seconds by an electronic timer in the RCA Dome. Gil Brandt, senior analyst for NFL.com and former Dallas Cowboys vice president of personnel, said Jones turned in the fastest time ever for a quarterback at the combine.
It was so fast the NFL Network, which used hand-held timers during its 2-hour broadcast, didn't announce Jones' time until several minutes after his first attempt. Jones, who was clocked at an unofficial 4.37 and 4.43 by the network, said he was told it was because they first thought it was a mistake.
"The first time, I heard (the NFL Network) wouldn't say my time because they didn't know it was right," Jones said. "That's like I'm saying, a lot of people don't believe I can do it. It's funny to me.
"They think their watch is broke or something or they messed up on the clock."
The Associated Press said Jones turned heads with his speed. Scout.com wrote that media members doubted Jones' claim he could run the 40 in 4.4, but said his "legend continues to grow" after his performance. ESPN.com's Len Pasquarelli said the times were amazing for a person that big and "few people are going to doubt Jones when he tells them he's going to do something now."
Jones credited his performance to his five-week stint at the Parisi Speed School in New Jersey. He understood how important his 40 time would be, began training in January and gave himself an opportunity to succeed in Indianapolis.
He might have gone to the combine with a reputation as a laid-back demeanor, but left being considered a hard worker. Dallas Cowboys owner and general manager Jerry Jones, a former Arkansas player, said Jones convinced scouts he will put in the effort needed to have a successful NFL career.
"Most every ambitious individual that comes into the NFL is aware and falls into the stepped up work ethic, the year-round commitment that is required," Jerry Jones said. "I don't care what kind of athlete you are or what kind of speed you've got. The players do it because of the rewards that are there.
"Matt's got every ability and does grasp that. Sure you're going to work more than you did in college because it's a full-time job."
Jones, who returned to Fayetteville on Sunday night, is planning to take a break for the first time since leaving for the Parisi Speed School. After a week, Jones will begin preparing for on-campus and individual workouts with NFL teams.
He has a private workout with the Jacksonville Jaguars scheduled for March 11 and will also participate in the on-campus pro date March 16. Jones likely won't run the 40 during the workouts, but he doesn't need to after turning plenty of doubters into believers with his speed at the combine.
"Whose to say he might not be (selected) in the first round, especially with people who have two picks," Arkansas coach Houston Nutt said. "I wouldn't let a luxury pick like that go by if you've got two guys in the first round.
"I think the sky is the limit (for Jones) right now."
Jones Exceeds Expectations
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